A new species of Stelletta from the southwestern Atlantic, Stelletta hajdui sp.n. is described from the slope off Rio Grande do Sul State coast, Brazil (32°24'S, 50°15'W) (Fig.1). The material studied was dredged up at the depth of 200m by the R/V Atlântico Sul, during “Projeto Talude” run by Fundação Universidade de Rio Grande (FURG). A key to the Brazilian Stelletta sponges is provided.